Documenting Police Shootings

Colleague Rick Hepp has a story today based on a review of police shootings over the last 12 months.

One conclusion:

The analysis found more than three-fourths of the 47 people shot at this year by state and local police were minorities.

Those who read this regularly (we know you're out there) will probably guess that, from my narrow statistical perspective, the most controversial number in that sentence isn't the "three-fourths", but the 47 -- can meaningful conclusions be drawn from such a small sample size?

Normally, the answer would be no. But there are two big reasons I can think of off the top of my head why the small sample size can't be used to dismiss the conclusion.

A) The disparity being documented is so stark that it can't likely be explained by random chance. The state's combined black/Latino population is 29 percent -- the police shooting stat is about 75 percent.

B) Despite the fact that our government seems to count everything, this is one category where reliable national figures (and a larger sample size) just doesn't exist. This was brought to light six years ago in an oft-cited New York Times story.

When I went hunting for a more recent take on police shootings data, I at first thought I had struck paydirt when I found a study on the Bureau of Justice Statistics home page titled: "Police Use of Force: Collection of National Data."

But that page links back to the inconclusive 1999 data and a more recent public survey where 6,400 people were asked about their interactions with police.

Needless to say, despite the BJS headline, this method didn't exactly yield any insights into police use of force:

Fourteen respondents of the 6,421 people questioned, representing approximately 500,000 residents nationwide, said police officers either warned them that force would be used or actually used force. Ten of the 14 also reported that some of their own actions, such as threatening the police or resisting being handcuffed, may have provoked police. The small numbers (7 of the 1,086 whites with police contact, 2 of the 97 blacks and 4 of the 74 Hispanics) made it impossible to reliably compare the use of force against persons of different racial or ethnic backgrounds.

Of course, it's certainly a good thing that there aren't enough police shootings to generate a large statistical sample. However, many believe that the shootings that occur need to be better documented and studied -- and not just along racial lines, but to answer questions such as: How often are police shootings deemed justified? How often do police shoot at moving vehicles? etc.

So in this category, an analysis of 47 cases is much, much better than nothing.